Interaction between Aromatics and Zinc Chloride. III. The Dissociation of Triphenylmethane and 9,10-Dihydroanthracene into Ions

Abstract

Triphenylmethane and 9,10-dihydroanthracene were found to produce colored complexes when placed in contact with molten zinc chloride or with solid zinc chloride pulverized or supported on porous Vycor glass. The triphenylmethane complex gave the same electronic absorption spectrum as that of the triphenylmethyl cation generated by contact with silica-alumina and BF3 on silica. The 9,10-dihydroanthracene complex exhibited the same electronic absorption band as that of the 9-anthracenium ion produced by the reaction of anthracene with concd H2SO4. The reaction of the triphenylmethane complex with deuterium gas provided HD gas and (C6H5)3CD. Similarly, the 9,10-dihydroanthracene complex and deuterium gas produced HD gas and 9,10-dihydroanthracene-9-d. Furthermore, their colored complexes on the supported zinc chloride gave a very weak IR absorption band at about 1720 cm−1, which is interpreted as corresponding to the formation of a Zn–H bond. These observations led us to conclude that triphenylmethane and 9,10-dihydroanthracene dissociate into ions . upon contact with zinc chloride: (C6H5)3CH+nZnCl2 \ightleftarrows (C6H5)3C+(ZnCl2)n−H (Remark: Graphics omitted.)

Antiaromaticity in Fluorenylidene Dications. Experimental and Theoretical Evidence for the Relationship between the HOMO/LUMO Gap and Antiaromaticity

“…However, oxidation with SbF 5 /SO 2 Cl 2 at −30 to 0 °C gave identical spectra, so data for oxidations in SO 2 Cl 2 at −30 °C are the ones reported here. The strongest absorptions for the UV−visible spectra of 1 − 7 and the absorptions for the corresponding monocations 8 − 14 for which UV−visible spectra are reported − are given in Table S2 in Supporting Information, along with the transitions calculated by TD-DFT spectra, using the 6-31G(d,p) basis set. TD-DFT calculations at the B3LYP/6-31G(d,p) level have been shown to give reasonable agreement with experimental spectra, with accuracies of 0.3 eV .…”